False-twist apparatus



Oct. 21, 1969 H. cRou zET FALSE-TWIST APPARATUS 3 Sheets-Sheet Filed May 7, 1968 0 7 I 2 2 I #m w I 5 6 4 a 0 L= VE T! R HENRI CROUZ ET his ATTORNEYS @ct. 23, 3969 H. CROUZET FALSE-TWIST APPARATUS 3 Sheets-Sheet 2 FIG. 4

85 FIG. 3 98 Filed May 7, 1968 his ATTORNEYS Oct. 21, 1969 H. CROUZET FALSE-TWIST APPARATUS 3 Sheets-Sheet E Filed May '7. 1968 MMM M INVESTOR.

HENRI CROUZET ATTORNEYS United States Patent 3,473,313 FALSE- V151 AtPARATUS Henri Crouzct, 15 Rue 'fiuvier, Roanne, Loire, France Filed May *1, 19dS,Ser.No. 727,216 Claims priority, application France, May 9, 1967, 105,776; Jan. 24, 1968, 137,279 lint. Cl. D0111 7/92, 7/46 US. Cl. 57-77.45 16 Claims ABSTRACT OF THE DTSCLUSURE This invention relates to an apparatus for driving elements at very high speed and, more particularly, to a new and improved apparatus for driving false-twist tubes or spindles at very high speed.

As is well known in the art, stretch fabrics are woven or knitted from a yarn having a permanent curl. A false-twist apparatus is utilized to attain the desired curl. The yarn is first twisted, and then by application of heat, for example, this twist may be permanently set in the yarn. The yarn is then untwisted and wound on a bobbin ready for weaving or knitting. Because of the permanent set in the untwisted yarn, which causes it to tend to return to its twisted condition, the desired stretch property is obtained in the woven fabric. The false twist is applied to the yarn by a rotating spindle or tube through which the yarn passes, the spindle being constructed so as to engage the yarn as it passes therethrough. It is apparent that the rate at which the yarn may be fed through the false-twist tube is limited by the rotational speed which can be imparted to this tube. Accordingly, considerable effort has been expended in the development of false-twist apparatus to increase the speed at which the spindles may be driven.

False-twist apparatus has been used in the past which supported the false-twist tube magnetically, however there are disadvantages in the prior art devices which limit the rotational speed at which such conventional devices may be rotated. For example, one known falsetwist apparatus includes a rotary cup-shaped member having two support rings projecting inwardly for the interior surface of the cup, the false-twist tube being retained against the support rings by means of a permanent magnet disposed outside of the cup. This arrangement is disadvantageous because the magnetic flux between the poles of the permanent magnet and the false-twist tube passes through the wall of the bowl, with the result that the magnetic field strength is reduced and undesirable heating occurs, particularly since the cup is made at least partly from synthetic resin.

Accordingly, is is an object of this invention to provide a new and improved false-twist apparatus which effectively overcomes the above-mentioned disadvantages of the prior art.

Another object of the invention is to provide an apparatus for rotating a shaft or the like at very high speeds, for example one million revolutions per minute or even faster.

A further object of the invention is to provide a falsetwist apparatus which is capable of rotating a yarn at Patented Oct. 21, 1969 considerably higher speeds than the conventional devices now is use.

These and other objects of the invention are attained by providing a false-twist tube or spindle of magnetizable material which is supported by an annular body member rotatable about the axis of the annulus. In particular, the body member carries at least one inwardly projecting ring, against which the spindle is urged outwardly by the poles of a permanent magnet, the poles being so disposed that the magnetic flux passes directly between the poles and the spindle without passing through any intermediate member.

Further objects and advantages of this invention will be apparent from the following detailed description in conjunction with the accompanying drawing showing the preferred embodiments, in which:

FIG. 1 is an elevational view, in section, of a typical false-twist apparatus in accordance with the invention;

FIG. 2 is a plan view of the apparatus of FIG. 1;

FIG. 3 is an elevational View, in section, of another embodiment of a false-twist apparatus according to the invention;

FIG. 4 is a plan view of the apparatus of FIG. 3, portions being broken away for clarity;

FIG. 5 is a sectional view of a portion of the apparatus of FIG. 4 taken along the line 55 of FIG. 4 and looking in the direction of the arrows;

FIG. 6 is an elevational view, in section, of still another embodiment of fa1se-twist apparatus according to the invention;

FIG. 7 is a plan view of the apparatus of FIG 6; and

FIG. 8 is a sectional view of a portion of the apparatus of FIG. 6 taken along the lin 8-8 of FIG. 6 and looking in the direction of the arrows.

In the typical embodiment of the invention shown in FIG. 1, a false-twist apparatus 10 comprises an annular body or cup-shaped member 11, which has an external hollow axial stem 12. The cup 11 is made from a nonmagnetic material and is preferably an aluminum alloy such as that known by the trademark Dural, which may be readily cast and machined so as to constitute a dynamically balanced assembly.

Disposed on an inwardly projecting flange 13 at the upper edge of the cup 11 is a bearing ring 14 made of a material which has a high coefficient of friction and is only slightly resilient, such as the material known by the trademark Vulcolan, which is a partially vulcanized polyurethane. The upper surface of the flange 13 is recessed or grooved so as to form a seat for a bearing ring 14, the inner annular bearing surface 15 of which is disposed radially inwardly of the flang 13.

The bearing ring 14 is held in place against the flange 13 by an annular block 17, and the lower edge of the block 17 is recessed to receive the bearing ring 14. The block 17 itself supports a retaining ring 19, and the facing inner edges of the block 17 and the ring 19 are recessed to seat a second bearing ring 20, which is preferably of the same material as the bearing ring 14. Furthermore, the inner annular bearing surface 22 of the bearing ring 20 is located radially inwardly of the block 17 and the ring 19. The ring 19, the block 17 and the flange 13 are secured together by press fits or by a plurality of screws (not shown), as desired.

The inner bearing surfaces 15 and 22 of the bearing rings 14 and 20, respectively, serve to support a falsetwist spindle or tube 25 made of a magnetizable material such as a ferrous metal, the tub being adapted to roll upon the bearing surfaces 15 and 22 as the cup 11 is rotated by means to be described below. The false-twist tube 25, which is outside the scope of the present invention, includes appropriate structure (not shown) for engaging the yarn passing therethrough, and preferably includes yarn entrance and exit apertures (not shown) as disclosed in my application entitled False-Twist Tube filed concurrently herewith.

The false-twist tube 25 is urged against the bearing rings 14 and 20 by means of a permanent magnet 27 which is supported by a post 29, the magnet acting through a pair of iron pole pieces 30 and 32 secured thereto. The pole piece 30 is disposed a small distance above the retaining ring 19, and the pole piece 32 is disposed inside of the cup 11 a small distance below the flange 13. The permanent magnet is preferably made from a titaniumcobalt-aluminium alloy of very high remanence, such as that known under the trademark Ticonal.

The hollow axial stem 12 of the cup 11 receives a hollow mounting tube 35, which is secured to the stem 12 and to a collar 37 by any suitable means such as a press fit. The cup 11 is driven by a belt 39 which is in driving engagement with the collar 37, which acts as a pulley. Mounted in the upper end of the hollow tube 35 is a bushing 41 which facilitates th passage through the tube of the yarn F to be subjected to false twisting. The bushing 41 is preferably made of an extremely hard material, such as a sintered aluminum.

The yarn is then deflected from the bushing 41 through a guide 43 at the end of an arm 45 which is pivotally mounted from the support 29. The position of the guide 43 may be adjusted by rotating the arm 45 as necessary, after which it may be locked in the desired position by the locking nut 46, so as to center the yarn precisely on the axis of the false-twist tube 25. The guide 43 is preferably also made from an extremely hard material, and both the guide 43 and the bushing 41 are highly polished.

Upstream of the false-twist apparatus illustrated is a suitable conventional heating element (not shown), and the false twist imparted to the twisted yarn by the heating element is set when the yarn cools. Downstream of the false-twist tube 25 the yarn, which is now in a high-bulk state, is normally reeled on a take-up bobbin (not shown). Optionally the yarn may be passed through a delivery means by which it is possible to regulate the tension of the yarn and to supply it, under the appropriate tension, to the take-up bobbin, This tension might also, but not necessarily, appear by a contraction occurring between the delivery means and the bobbin. It is also possible to provide a second heating element between the delivery means and the bobbin in order to produce a stabilized bulked yarn.

The poles 30 and 32 of the permanent magnet 27 may be provided with concave surfaces concentric with, and facing, the false-twist tube 25 in order to improve the centering of the false-twist tube, i.e., in order to minimize any tendency of the false-twist tube to wobble. Furthermore, the poles of the permanent magnet are preferably so spaced that the magnetic flux travels through the entire length of the spindle 25.

With this false-twist apparatus, the heating of the metal, and especially the heating of the false-twist tube, is negligible even when the false-twist tube is rotated at velocities of the order of one million revolutions per minute. Nevertheless, an air circulation or other cooling arrangement could be provided in conjunction with the falsetwist apparatus, if desired.

FIGS. 3, 4 and illustrate another embodiment of the invention, in which the pole pieces of the magnet act on the false-twist tube between the pair of bearing surfaces as contrasted with the first embodiment in which the pole pieces act on the tube externally of the bearing surfaces. The false-twist tube 50 includes a cast and machined cup 52 made from a light non-magnetizable alloy and secured to a pulley '54 driven by a driving belt 55.

The cup 52 includes a stepped lower portion 58, an outwardly extending central portion 59 and an upper portion 60 which has a larger diameter than does the lower portion 58. The interior of the central portion 59 is recessed to receive an annular disk 62, which in turn supports an- 4 other annular disk 64. The two disks 62 and 64 are secured by a plurality of screws 66 to the central portion 59 of the cup 52. The two disks 62 and 64 are recessed at their inner opposed faces to receive a bearing ring 68. the inner annular bearing surface 70 of which is disposed radially inwardly of the disks 62 and 64.

Above the disk 64, and inside of the upper portion 60 of the cup 52, is a cylindrical block 72 which wedges an annular disk 74 against an inturned flange 76 at the upper edge of the upper cup portion 60. An annular cover 78 is disposed on the disk 74 in registry with the flange 76v and a second bearing ring 80 is received in complementary grooves formed in the disks 74 and 78, in a manner similar to the mounting of the bearing ring 68. The disks 74 and 78 are secured together by a plurality of screws 79. The inner annular bearing surface 81 of the bearing ring 80 is disposed radially inwardly of the disks 74 and 78.

A circular permanent magnet 85 is disposed in the annular cavity formed by the disk 64, the cylindrical block 72 and the disk 74. The magnet 85 has two pole pieces 86 and 87 which urge a false-twist tube '90 against the annular bearing rings 68 and 80. The tube 90 is preferably of the type described in my application entitled False-Twist Spindle filed concurrently herewith.

The magnet 85 is supported by a fixed bracket 93 disposed outside of the cup 52 through a connecting member 95 having a laterally extending shoulder 96, to which a supporting arm 98 of the magnet is secured by a screw 99. The connecting member 95 also has a lower lateral shoulder 101 which rotatably supports, by means of the bearings 102, the upper end of a hollow tube 103 secured to the pulley 54, the tube 103 also beingsupported in a base structure 104 by means of the bearings 105.

The yarn F which is to be subjected to false twisting enters the cup 52 through the hollow tube 103, and is then deflected so as to pass through an eyelet 106 mounted on a guide arm 107. The guide arm is adjustably mounted on the connecting member '95 so that the position of the eyelet 106 may be adjusted to center the yarn F in the axis of the false-twist tube 90. The yarn then proceeds from the false-twist tube to the delivery means (not shown) and thereafter to the take-up bobbin (not shown).

The false-twist apparatus of the second embodiment permits the false-twist tube to be rotated at one million revolutions per minute and even more when the cup 52 is rotated at approximately fifty thousand revolutions per minute. At these speeds the rotation of the false-twist spindle is extremely stable, and the spindle is stabilized vertically and laterally. To this end, the poles 86 and 87 of the permanent magnet are preferably provided with concave surfaces 110 concentric with the spindle 90.

FIGS. 6, 7 and 8 illustrate the third embodiment of the invention. Here the false-twist apparatus is mounted on a vertical shaft 117 secured to a fixed support 118. Mounted on the shaft 117 is a hollow skirt 120 which depends from an axial stem 122, the skirt 120 being rotatably mounted on the shaft 117 by means of two antifriction bearings 123 and 124.

A first cup 126, which opens upwardly, is integral with the skirt 120, and a second cup 128, which opens downwardly and is formed with at least two apertures or ports in the top 132 of the cup 128, the apertures 130 being spaced symmetrically about the axis of the axial stem 122. The upper cup 128 is keyed to the upper portion of the axial stem 122 for rotation therewith.

Extending radially inwardly from the upper rim of the lower cup 126 is a flange 134 formed with an annular groove containing an annular bearing ring 136. The hearing ring 136 is secured against the flange 134 by a retaining ring 138, the retaining ring being secured to the lower cup 126 by a force fit or a plurality of screws (not shown). as desired. The annular bearing surface 139 of the bearing ring 138 is disposed radially inwardly from the flange 134 and the retaining ring 138.

Similarly, the upper cup 128 includes a flange 141 extending radially inwardly from the lower rim thereof.

and an annular bearing ring 143 is held against the flange 141 by a retaining ring 145. The annular bearing surface 147 of the bearing ring 143 is disposed radially inwardly of the flange 141 and the retaining ring 145.

Two permanent magnets 151 and 151 are disposed adjacent the cups 126 and 128, and the two poles N and S extend between the opposed flanges 134 and 141 of the bowls 126 and 128, respectively. Two diametrically opposite false-twist tubes 154 and 155 are urged against the annular bearing surfaces 139 and 147 by the poles of the permanent magnets 156 and 151, respectively. As before, the false-twist tubes 154 and 155 are of magnetizable material and are preferably of the type disclosed in my application entitled False-Twist Spindle filed concurrently herewith. The cups 126 and 128 are driven by a belt 156 which is in driving engagement with the skirt'12il, which serves as a pulley.

Adjacent each false-twist tube is a vertical rod 158 secured to a fixed support 159 which may be positionally adjusted, as desired. (The right-hand rod 158 and the as- H sembly associated therewith have been omitted from FIG. 6 for clarity.) Pivotally mounted on the rod 158 is a support member 160, which carries upper and lower vertical eyelets 162 and 163, the axes of which are horizontal, and upper and lower horizontal eyelets 164 and 165, the axes of which are vertical.

FIG. 8 best illustrates the travel of the yarn F through the false-twist apparatus of this embodiment. The yarn enters between the two cups 126 and 128 through the lower eyelets 163 and 165, up through the false-twist spindle 154, after which it passes through the upper eyelets 164 and 162, and then it is withdrawn laterally through the space between the cups.

Prior to entering the illustrated false-twist apparatus, the yarn is heated by an appropriate heating element (not shown) while it is subjected to false twisting, and this false twist is fixed on cooling, prior to untwisting. It is to be understood that the ath of the yarn F illustrated in FIG. 8 is diagrammatic, inasmuch as the true path of the yarn does not lie in the plane of the drawing.

The false-twist apparatus according to the third embodiment has the advantages that the spaced cup arrangement permits the permanent magnets to be of relatively simple construction and contributes to the ventilation of the apparatus.

Although this invention has been described with reference to the foregoing specific embodiments, it will be understood that various substitutions, changes and modifications in the form and details of the apparatus illustrated and its manner of employment may be made by those skilled in the art without departing from the spirit of the invention. For example, one or more additional magnets could be employed with the disclosed embodiments so that two or more spindles could be simultaneously rotated, the magnets preferably being so located that the ole pieces are symmetrically disposed about the axis of revolution of the driving member.

I claim:

1. Apparatus for rotatin a spindle, at least a portion of which is of magnetizable material, comprising driving means having at least one continuous spindle-engaging surface facing inwardly thereof and magnet means for urging the spindle outwardly against and in driving engagement with the spindle-engaging surface of the driving means, the magnet means being so disposed that the magnetic fiux passes directly between the magnet means and the spindle.

2. Apparatus according to claim 1 wherein the driving means comprises a rotatable member having an internal circular spindle-engaging surface adapted to engage the spindle.

3. Apparatus according to claim 1 wherein the driving means comprises a rotatable member having a pair of spaced internal circular spindle-engaging surfaces adapted to engage the spindle.

4. Apparatus according to claim 1 wherein the magnet means are formed with pole pieces spaced in close proximity to the magnetizable portions of the spindle, the pole pieces being disposed on opposite sides of the spindle-engaging surface.

5. Apparatus according to claim 3 wherein the magnet means are formed with at least one pole piece spaced in close proximity to the magnetizable portions of the spindle, the pole piece being disposed between the spindleengaging surfaces.

6. Apparatus according to claim 1 wherein the magnet means are formed with at least one pole piece spaced in close proximity to the magnetizable portion of the spindle, the pole piece being formed with a concave surface facing and substantially concentric with the spindle.

7. Apparatus according to claim 1 wherein the spindleengaging surface is formed by a material having a high coefiicient of friction.

8. Apparatus according to claim 1 wherein the driving means is an annular member rotatable about the axis of the annulus and provided with an external axial stem carrying a pulley by means of which the annular member may be rotated.

9. Apparatus according to claim 8 wherein the magnet means includes two pole pieces disposed on opposite sides of the spindle-engaging surface, one pole piece being disposed inside of the annular member and the other pole piece being disposed outside of the annular member.

10. Apparatus according to claim 8 wherein the annular member has a pair of spaced internal circular spindle-engaging surfaces and the magnet means includes two pole pieces disposed inside of the annular member and between the spindle-engaging surfaces.

11. Apparatus according to claim 3 including means for guiding yarn through the spindle, the guiding means being adjustably positioned inside of the annular member.

12. Apparatus according to claim 1 wherein the driving means includes two cupshaped members spaced from and open towards one another and mounted for rotation together about a common axis, a bearing ring adapted to engage the spindle extending inwardly from the rim of each cup-shaped member, and wherein the magnet means is formed with at least one pole piece extending between the bearing rings.

13. Apparatus according to claim 12 including at least one additional magnet means having at least one pole piece extending between the bearing rings, the pole pieces being disposed symmetrically about the axis of the cupshaped members, so that a plurality of spindles may be simultaneously rotated by the cup-shaped members.

14. Apparatus according to claim 12 wherein the pole piece is formed with a concave surface facing and substantially concentric with the spindle.

15. Apparatus according to claim 12 including means for guiding yarn through the spindle, the guiding means being adjustably positioned inside of the cup-shaped members.

16. Apparatus according to claim 15 wherein the guiding means is disposed adjacent the ends of the spindle so as to guide the yarn between the bearing rings to and from the spindle.

References Cited UNITED STATES PATENTS 3,180,074 4/ 1965 Smith 5777.45

3,292,357 12/ 1966 Richter 5777.45

FOREIGN PATENTS 1,268,325 6/ 1961 France.

1,366,012 6/1964 France.

1,468,585 12/ 1966 France.

1,031,665 6/1966 Great Britain.

DONALD E. WATKINS, Primary Examiner 

